The effects of protein malnutrition on the course of Leishmania mexicana infection in C57Bl/6 mice: nutrition and susceptibility to leishmaniasis.

The course of cutaneous infection with Leishmania mexicana was studied in normally nourished and protein deprived C57Bl/6 mice. Mice fed a normal diet showed self-resolving lesions and produced cellular and humoral responses against the parasite. In contrast, mice fed a protein deficient diet which developed chronic protein calorie deficiency failed to recover from L. mexicana infection. Non-healing protein deprived mice had depressed delayed hypersensitivity response (DHR) and in vitro lymphocyte reactivity to leishmanial antigen. Responses to PHA and Con A were also suppressed. The possible interaction between malnutrition, impairment of the immune response and chronicity of cutaneous leishmaniasis is discussed.